346 



mi. R. BROOM ON SOME NEW 



they are not anehylosed. Eacli Jias an ascending thin plate and 

 a short descending plate, and from each bone a transverse plate 

 passes outwards which approaclies and doubtless further back 

 meets the palatine. The palatines as seen here in section are 

 slender curved bones which below meet the maxillaries, and on 

 passing inwards and then upwards again approach and possibly 

 meet the upper borders of the maxillaries. 



The prevomers extend backwards a considerable distance 

 behind the plane of the last molars and meet the anterior ends of 

 the pterygoids. The palatines form the greater part of the bony 

 roof of the mouth, passing about as far back as the posterior end 



Text-figure 3. 



Palatal surface of skull of Ictidosticlms longieeps Broom. 



of the maxilla. There is behind the palatine a large suborbital 

 vacuity as in Scylacosaurus, and, as in that genus, this vacuity is 

 bounded externally by the ectopterj^goid. The ectopterygoid is 

 moderately slender, but in front of the pterygoid process which 

 lies along the inner side of the mandibles it has a well-developed 

 descending process, which adds much support to the pterygoid 

 process. 



The pterygoid is fairly similar to that already described and 

 figured by me in Scylacosauriis, and possibly some of the apparent 

 differences may be due fo certain features being preserved in the 

 present specimen which were lost in the other. As in most 

 primitive reptiles, there is an anterior process which, passing 



